In typical commercial electrographic reproduction apparatus (copier/duplicators, printers, or the like), a latent image charge pattern is formed on a uniformly charged charge-retentive or photoconductive member having dielectric characteristics (hereinafter referred to as the dielectric support member). Pigmented marking particles are attracted to the latent image charge pattern to develop such image on the dielectric support member. A receiver member, such as a sheet of paper, transparency or other medium, is then brought into contact with the dielectric support member, and an electric field applied to transfer the marking particle developed image to the receiver member from the dielectric support member. After transfer, the receiver member bearing the transferred image is transported away from the dielectric support member, and the image is fixed (fused) to the receiver member by heat and pressure to form a permanent reproduction thereon.
One type of fuser assembly, utilized in typical reproduction apparatus, includes at least one heated roller and at least one pressure roller in nip relation with the heated roller. The fuser assembly rollers are rotated to transport a receiver member, bearing a marking particle image, through the nip between the rollers. The pigmented marking particles of the transferred image on the surface of the receiver member soften and become tacky in the heat. Under the pressure, the softened tacky marking particles attach to each other and are partially imbibed into the interstices of the fibers at the surface of the receiver member. Accordingly, upon cooling, the marking particle image is permanently fixed to the receiver member.
When a receiver member is fused, it picks up quite a considerable amount of heat. As the fused image bearing receiver member travels along the transport path it looses some of the stored heat, thus heating up other elements of the reproduction apparatus. This tends to adversely effect the reproduction apparatus elements making them less dependable. As a result, receiver member jams may occur more often. When the receiver member finally comes to rest in a suitable output tray, other fused image bearing receiver member usually follow to form an output stack. As a result, heat stored in the receiver members will increase the overall temperature of the receiver member stack. Tests have shown that if this temperature is higher than 140.degree. F., the marking particles of one receiver member tends to sticks to the next receiver member, making several reproductions undesirably stick together to form a "brick". Accordingly, it has been the general practice to provide an extended travel path for fused image bearing receiver members, or a cooler device directly following the fuser (see for example U.S. Pat. No. 5,221,200, issued on Jun. 22, 1993, in the name of Roztocil et al). The extended transport path enables a receiver member reaching the stack to have somewhat cooled down as it travels along the transport path before reaching the stack. However, the extended transport path may undesirably increases the size of the reproduction apparatus. On the other hand, the prior art cooler devices have not always been efficient enough to yield the required receiver member temperature reduction for a reasonable size, power consumption, and noise generation.